As posted above, you can't go wrong with grammostola aureostriata. Also good would be grammostola pulchra (Brazillian Black), but they are more expensive unless you are looking at a sling. Grammostola Rosea (Chilean Rose) is readily available and generally docile as well. Of course, there are always risks with handling any tarantula, because of urticating hairs as well as the potential for being bitten. Also, dropping a tarantula is likely to prove fatal.